• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.1053-1057
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• 2005

현재 IETF (Internet Engineering Task Force)의 SHIM6 (Site Multihoming by IPv6 Intermediation) 워킹그룹에서는 Network layer Shim (L3shim)이라는 새로운 IPv6 스택을 정의하여IPv6 환경에서 멀티호밍을 지원하는 방법에 대해 표준을 제정하고 있다. 이 Multihoming은 redundancy, load sharing과 같은 멀티호밍 장점을 지원할 수 있다. 본 논문은 이와 같이 새롭게 정의된 L3shim이 단말에 있을 경우, 단말에서 효과적인 Policy 정책을 통한 load sharing 및 balancing 통한 traffic engineering 방법을 제시한다. 현재 SHIM6 워킹그룹에서는 L3shim을 이용한 load balancing 부분은 다루고 있지 않다. 그러나 멀티호밍의 장점 줌 하나는load balancing이며 실제 load balancing이 지원 됐을 경우 응용 차원에서 많은 장점을 가질 것으로 여겨진다. 따라서 이와 관련한 메커니즘이 필요하며, 이를 위한 선행적인 연구가 필요로 되어진다.

• Bulletin of the Korean Chemical Society
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• v.9 no.6
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• pp.410-410
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• 1988

• Journal of the Korean Applied Science and Technology
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• v.6 no.1
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• pp.9-14
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• 1989

Effectiveness of some natural antioxidants were investigated by measuring the physico-chemical charcteristics and fatty acid composition during thermal oxidation in palm oil. Tocopherol showed most enhanced thermal oxidation stabilities compared to the other natural antioxidants. AR spice was no good AOM stability and changes of acid value but the other parameters were obtained desirable results. The changes of linoleic aicd content was slightly decreased during thermal oxidation. Addition of rosemary and glycyrriza extract increased the stabilities of oil less than tocopherol and AR spice. Order of antioxdative effects was tocopherol, AR spice and others. There was no significiant difference in stability of rosemary and glycyrriza extract.

• Journal of Korean Neurosurgical Society
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• v.61 no.2
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• pp.287-288
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• 2018

• Journal of Electrical Engineering and information Science
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• v.2 no.6
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• pp.95-105
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• 1997

In this paper, we have studied about design and fabrication of the actively shielded superconducting MRI magnet. Nonlinear optimization methods are usually used to find optimum coil configurations. However the selection of initial coil configurations is very difficult. In case bad initial data are used, it is even impossible to find optimum coil configurations which satisfy predefined constraints. We have developed computer optimization program which consists of two steps. Initial coil configurations are easily selected through linear optimization in the first step and optimum coil configurations are found through nonlinear optimization in the second step. We have also studied about superconducting shim coils to cancel error fields caused by coil fabrication errors. Many researchers published design concepts of shim coil. However all these studies are for shim coil design using filamentary coils with single turn, Shim coils with multi-turns should be used to produce enough field strength to cancel error fields. We have developed computer program for the design of shim coils which have proper thickness and length. An actively shielded superconducting MRI magnet with a small warm bore was fabricated and four sets of superconducting shim coils were equipped. The magnetic field distributions were measured and field correction was carried out using shim coils.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.481-485
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• 1993

Dialkyl 1-bromobenzene-2,6-diacetates were easily prepared by the carbonylation of the moiety of benzylic bromide in 1-bromo-2,6-bis(bromomethyl)benzene with alcohol in the presence of NaOAc< TEX>${\cdot}$3H$_2$O and a catalytic amount of Co$_2$(CO)$_8$under the atmospheric pressure of carbon monoxide at room temperature in excellent yield. Alkyl 2,6-bis(alkoxymethyl)benzoates were obtained by the carbonylation of the moiety of aryl bromide in 1-bromo-2,6-bis(alkoxymethyl)-benzene, which derived from 1-bromo-2,6-bis(bromomethyl)benzene, alcohol, NaOR, and CH$_3$I under the same conditions. Alkyl 2,6-bis(carboxymethyl)benzoate was also obtained in a trace amount for 24 hrs at room temperature.

• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.513-515
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• 1994

• Bulletin of the Korean Chemical Society
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• v.5 no.6
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• pp.265-266
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• 1984

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.511-511
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• 2019

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.2867-2872
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• 2012

SAN/$BMIPF_6$ nanofibers were fabricated by an electrospinning process and used as chemiresistors for sensing alcohol vapours. A hydrophobic and air-stable ionic liquid, $BMIPF_6$, was used to impart electrical conductivity to insulating SAN nanofibers. The effects of $BMIPF_6$ addition on the morphology of the nanofibers were explained in terms of surface tension, viscosity and conductivity. After exposing the SAN/$BMIPF_6$ nanofibers collected on an interdigitated electrode to alcohol vapours (ethanol, 1-propanol and 1-butanol), the resistance of the nanofibers decreased due to adsorption of alcohol molecules. The electrospun SAN/$BMIPF_6$ nanofibers sensor exhibited good sensitivity and reproducibility.